Equity - Changes to Redeemable Noncontrolling Interest (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance at beginning of period			$ 1,620
Net income attributable to noncontrolling interest	$ 44	$ 36	128	$ 112
Capital contribution from noncontrolling interest			36
Distributions payable to noncontrolling interest			(115)
Redemption value adjustment			356
Balance at end of period	$ 2,025		$ 2,025

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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- Definition

Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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